Apparatus for the conversion of flat netting into labeled bags



Sept. 5,1967 D. R. M GREGOR 3,339,506

APPARATUS FOR THE CONVERSION OF FLAT NETTING INTO LABELED BAGS Filed Feb. 18, 1965 3 Sheets-Sheet 1 M Q N Sept. 5, 1967 D. R. MGGREGOR 3,339,506

APPARATUS FOR THE CONVERSION OF FLAT NETTING INTO LABELED BAGS Filed Feb. 18, 1965 3 Sheets-Sheet 2 Sept. 5, 1967 o. R. M GREGOR 3,339,506

APPARATUS FOR THE CONVERSION OF FLAT NETTING INTO LABELED BAGS Filed Feb. 18, 1965 3 Sheets-$heet United States Patent APPARATUS FOR THE CONVERSION OF FLAT NETTING INTO LABELED BAGS Donald R. McGregor, New Providence, N..I., assignor to E. I. du Pont de Nemours and Company, Wilmington, Del., a corporation of Delaware Filed Feb. 18, 1965, Ser. No. 433,579

1 Claim. (Cl. 112-10) ABSTRACT OF THE DISCLOSURE An apparatus for converting fiat netting into labeled bags comprising a set of continuous belts advancing a double layer of netting, a label source, a pair of sewing machine heads sewing the edges of the netting and the label, a cutter severing the sewn netting into individual bag lengths, means for arranging the individual bag lengths in side-to-side relationship, another set of continuous belts advancing the bag lengths, and another sewing machine head sewing one edge of the advancing bag lengths to define the bottom thereof.

This invention relates to bags and more particularly to an apparatus for converting flat netting into sewn bags.

There is a serious need in the trade for a machine that can continuously produce bags from unsupported, nonrigid, flat netting or similar structures because such material is difiicult to move mechanically without wrinkling or otherwise distorting its shape. Although sewing is a relatively simple and cheap operation, the nature of the material to be handled normally dictates a partially manual operation.

It is therefore an object of this invention to provide an apparatus for producing bags from flat netting or similar structures. It is a further object to provide means for continuously handling such material without distorting it. It is a further object to rapidly convert flat netting of various types into bags sewn on three sides in a continuous, economical fashion. Other objectswill become apparent from the following description.

The apparatus for accomplishing the objects of this invention includes means for continuously advancing a double layer of flat netting, means for sewing each edge of the advancing double layer of netting, means for cutting the continuous sewn netting to sever said netting into individual bag lengths sewn on each side, means for arranging and continuously advancing said individual bag lengths in side-to-side relationship and means for sewing one edge of the advancing side-to-si-de bag lengths to close one end thereof and form bags sewn on three sides and open on one side.

A preferred embodiment is to have means for applying a label substantially from edge to edge of the advancing netting so that the initial sewing means will sew both the edges of the netting and the corresponding edges of the labels.

Since the final sewing means, closing one end of the bag lengths, leaves a thread connecting the sewn ends together, it is also preferred that there be provided a means for cutting the thread between said sewn ends.

Apparatus for carrying out this invention is shown by way of example in the attached drawings in which:

FIGURE 1 is a perspective view of a preferred form of apparatus for carrying out the present invention;

FIGURE 2 is a plan view of the apparatus shown in FIGURE 1;

FIGURE 3 is a side elevation of the apparatus shown in FIGURE 1;

FIGURE 4 is a sketch of a bag produced by the preferred process embodiment;

FIGURE 5 is a sketch of a bag produced from one layer of netting and one layer of high tear paper or poly; and

, FIGURE 6 is a cross-sectional view taken along line 66 of FIGURE 5.

, Referring in more detail to the drawings, a first set of parallel continuous belts 2 continuously conveys a double belts 2 will not interfere with the sewing operation. As

the double layer of netting is advanced, the label source 4 cuts and drops a label on top of the netting extending substantially across the width thereof, i.e., from edge to edge of the netting. The sewing machine heads 6 and 8, situated above the opposing edges of the advancing netting, then sew each edge of the netting and the corresponding edges of the label together to define the sides of the subsequently formed bags.

Located beyond the sewing machine heads 6 and 8,

adjacent the end of belts 2, are means for cutting the advancing sewn netting transversely to its initial direction of travel to sever the netting into individual bag lengths sewn on each side. The means shown comprises a rotary cutting knife 16 which severs the netting against cutting edge 18. The speed of rotation of cutting knife 16 can be adjusted to give the desired bag length. As each bag length is cut, it slides down arcuate surface 20 onto star wheels 22 and 24. The star wheels make a 90-degree intermittent motion for each revolution of cutting knife 16, thereby dropping a single bag length onto a second set of parallel continuous belts 26. The second set of belts 26 continuously conveys the bag lengths, at right angles to their initial direction of travel, in a side-toside relationship. The purpose of the star wheels 22 and 24 is to hold the net as it is being cut so that it will not be moved by belts 26 until it is free to move sideways in proper alignment, and to drop the net to the lower set of belts 26 at the proper time to give the desired side-byside spacing. The rotary knife 16 passes between star wheels 22 and 24 during each revolution. The cutting and dropping of labels by the aforementioned label source 4 is synchronized by an electric switch (not shown), or other conventional means, with the rotation of rotary cutting knife 16 to drop a label in the desired location for each bag.

The individual labelled bag lengths, sewn on each side, are next conveyed by belts 26 under and past another sewing machine head 10. Belts 26 are also spaced apart to leave a narrow passage 14 so that belts 26 will not interfere with the sewing operation of sewing head 10. The sewing machine head 10, positioned above one edge of the advancing bag lengths, sews one edge of the advancing side-to-side bag lengths to define the bottom of the bags. In the preferred embodiment shown, a thread cutter 28 is located at the far end of the second set of belts 26 to sever the thread connecting the sewn bottoms of the 32. The movable knives 30 have intermittent movement 'bag. Or, if no labels are desired, the initial sewing operation could be dispensed with entirely. However, the apparatus of this invention is more uniquely suited to the conversion of double layer fiat netting into bags. It can be plastic netting of any type, i.e., with diamond, square or other mesh design, having been made by integral or non-integral extrusion or by other means. The netting can also be made of twisted paper or string. In any of these cases, one of the layers could be of a different material, such as plastic film, paper or textile material.

The label stock is preferably a high-tear paper such as alatex paper, poly coated paper, a paper of synthetic polymeric fibers such as polyethylene, polypropylene or a polyamide. This label stock could also be a heavy guage polyethylene film, crepe paper or paper-metal foil laminates. It may also be preferred to use no additional label at all, e.g., one layer of feed could be netting and the other of high tear paper or poly which could be printed on to serve as the label to produce a bag 42 as shown in FIGURES 5 and 6.

With conventional commercial sewing heads, about 80 feet per minute is the maximum speed, and 30 feet per minute is common. Modification of the sewing heads would be necessary to achieve greater speeds. Regardless of the speed, the feeding and take-off speeds must be synchronized in such a way that the cut bags will be aligned properly on the second set of belts 26 and taken away fast enough to prevent a build-up of cut bags below the star wheels 22 and 24.

In the preferred embodiment, when using a double layer of flat netting, it is preferred to use a chain stitch. When one of the layers is a film, paper or textile material, other stitches such as back-stitch, cross-stitch and knotstitch are also adequate.

The moving sets of belts 2 and 26 are arranged as shown so that sewing can be done between the belts. In this way the netting can be supported across its width and length throughout the sewing operation. Not shown for clarity, but desirable, is another belt above each set of belts 2 and 26 to hold the netting and label flat during sewing and advancing. The belt above the first set of belts 2 would have a width less than the distance between sewing heads 6 and 8 so as to not interfere with the sewing operation. In place of the first set of belts 2, one continuous belt passing just inside the sewing heads could be used. With this arrangement, the edges of the netting could be allowed to hang freely over the sides of the belt, or parallel guide rails could be provided to support the edges of the netting. A similar substitution could be made for the second set of belts.

The label feed and other parts of the apparatus can be controlled so that the label is applied to the center of each bag or to one end of the bag as a header label.

The star wheels 22 and 24, in the apparatus shown, are below the feed level of the upper belts 2 primarily to provide space for rotation of knife 16. Thus, if a diflFerent kind of cutter is used, such as a guillotine-type, the axes of star wheels 22 and 24 could be on the same level as belts 2, or at various levels and angles with respect to belts 2. Thread cutter 28 could also be replaced by other conventional cutting means.

Thus, it can be seen that the apparatus of this invention has the advantage that non-rigid fiat netting of various types can be rapidly and continuously converted into strong, uniform bags in a very economical fashion. The bags produced are useful in a variety of packaging uses, particularly for bagging produce.

It is to be understood that the foregoing description is by way of example only and that various modifications and changes in the details may be made without departing from the spirit of the invention and the scope of the ap pended claim.

What is claimed is:

An apparatus for converting flat netting into labelled bags comprising means for continuously advancing a double layer of said flat netting, means for applying a label to said advancing double layer of flat netting, whereby said label extends substantially from edge to edge thereof, means for sewing each edge of the advancing double layer of netting and the corresponding edges of the label, means for cutting the continuous sewn netting to sever said netting into individual labelled bag lengths sewn on each side, means for arranging and continuously advancing said individual labelled bag lengths in side-to-side relationship and means for sewing one edge of the advancing side-to-side labelled bag lengths to close one end thereof and form labelled bags sewn on three sides and open on one side.

References Cited UNITED STATES PATENTS 1,054,867 3/1913 Plass 112-10 1,187,057 6/ 1916- Foster 11210 1,768,126 6/ 1930 Maier 112 10 1,884,032 10/ L932 Maier 11210 1,929,970 10/ 1933 Floyd 1l2 10 2,940,404 6/1960 Damon 112l0 3,126,848 3/ 1964 Gastonguay.

JORDAN FRANKLIN, Primary Examiner.

A. GUEST, Assistant Examiner. 

